Love and trust are fine but a story becomes gripping when betrayal is introduced. Some of the greatest villains of all time have been traitors, double crossers or simply rascals who betrayed the people who trusted (and sometimes loved) them.

William Shakespeare adored betrayal and Iago’s slow, calculating deceit of Othello is perhaps the greatest illustration of evil ever written. King Lear is a play particularly dominated by savage betrayal. The Bible is full of betrayal from Delilah to Judas Iscariot – the most infamous traitor of them all – who did the awful deed with kiss. In Greek literature, there is a betrayal at every turn - Aeneas betrays Dido, Clytemnestra betrays Agamemnon and Ephialtes betrays the Spartans by helping the Persians at the Battle of Thermopylae.

Brutus betrays Julius Caesar and stabs him in the back - how many times is that phrase used in everyday conversation? Cold War spy novels would be worthless without the double and triple agents – the reader expects it and attempts to work who is double crossing who as the plot unfolds. The Cato Street Plotters, Guy Fawkes, Benedict Arnold, Kim Philby, Anthony Blunt, William Joyce, Mata Hari, Vidkun Quisling – the list goes on and on.